Watt-hour meter phase adjuster



June 20, 1950 R. M. LEIPPE WATTHOUR METER PHASE ADJUSTER Filed April 30. 1947 p A; Y Z M mmflm i MW any 7 3 WITNESSES Patented June 20, 1950 U NITED STATES 2,512,345 WAr nnoUR METER PHASE, ADJUSTER Richard M. Leippe, Cedar Grove, 3., assignor to Westinghouse Electric Corporation, East Pittsburgh, Pa e. corporation of Pennsylvania Application April 30, 1947 Serial-No. 745,023

(C1. Thy- 34) 19 Claims.

This invention relates to'a device for establishing a predetermined displacement between the magnetic flux components ofa shifting magnetic field and it has particular relation to a la ing or quadrature adjusting member for establishin the'correct displacement between the voltage and current magnetic fluxes of an alternating-current watthour meter. 7

In accordance with the invention, a lagging member is provided for establishing a desired phase displacement between the magnetic flux components of a shifting magnetic field. This lagging member is movable for the purpose of adjusting the phase displacement and'preferably is rotatable for adjustment purposes. When the lagging member is employed for establishing the correct phase displacement between current and Since rotation of the lagging member tends to vary somewhat the pattern of the magnetic fluxes, such rotation under some conditions might tend to alter the light load performance df the watthour meter. By proper selection of the axis of rotation of the lag ing member, the light load adjustment of the watthour meter can be made substantially independent of the adjustment of the lagging member.

Conventional watthour meters have magnetic shunts associated therewith for the purpose of controlling the load response of the watthour meter. In accordance with a further aspect of the invention, the lagging member is vrota'tably secured to the magnetic shunt of a watthour meter to constitute a unit which is detachably associated with the magnetic structure of the watthour meter. 1 7

It is, therefore, an object of the invention to provide an improved device which is movable for the purpose of adjusting the phase displacement between the magnetic flux components of a shifting magnetic field.

It is afurther object ofthe invention toprovid'e a lagging-member in the --form of. an annular electroconductive rim having an 'electrocbnductive bar extendingthereacr'oss. v I

It is a sun "further object'of "the invention to rovidea watthourm'e'ter lagging member which is movable for adjusting the 'pha'sedisplacement between the magnetic fluxes of 'ashifting mag netic fieldthi'dugh apathsuch that the" light lbad adjustment of "the associated watthour meter is substantially independent of such movement.

It is also an object Of the "inventi n to provide watthour meter havlng'a'ssobiated therewith as a detac'l'iable unit am'agneti'c shuntand a lagging meiriberr'dtatably"secured to the shunt.

It'is another object of the invention to provide an adjustable watthour meter lagging member which ma .be moved to adjust the light load response of a watthour meter.

Other objects of the invention willbe apparent from the'follo'wing detailed description, taken in cohjuntibn with the accompanyingdrawin in which:

Figure 1 is aview infront' elevationof a watthour meter embodying the invention;

Fig. 2 is a sectional view. With'pa'rts broken away, taken along the line'lI lI offFi'g. 1;

Fig. 3 a view similar to Fig. 2, but with an adjustable part shown in a different position; and

Figs.'4, 5 and 6 are views similar to Fig.2 showing different constructions for certain parts thereof. v

Referringto the drawingFig. 1 'sho'ws'a watthour meter having a magnetic structure "I This magnetic structure includes a voltage magnetic ,p'o1e"3havin'g.a pole face 5. "Themagnetic structure alse includes a'p'air of current magneticfipole pieces I 'a'nd'9 having pole faces H and I3. By

inspection of Fig. 1, it will be observed thatthe pole faces H and [tarefiisposedin a common plane which is spaced from (the 'pole face 5 to define "an 'air gap [5 in whichan electroconductive armature in the form of a disk l'l' isdisposed. Conveniently, the disk ll maybe mounted on a shaft is for'rotation in a-manner well understood in the art,

Inorder to direct magnetic fiu'x' through the air gap E5, the voltage magnetic po'le '3 is surrounded by a voltage winding It. When the voltage winding 19 is energized from a source of alternating voltage, an alternating voltage magnetic flux is established which traverses the air gap [5 and the disk H positioned in the air ga Such magnetic flux is represented in Fig. 1 by dotted lines 21 and 23 which have arrdws associated therewith for the purposeof indicating an instantaneous direction "of flux 116W. it w ill dotted line 23 traverses the air gap I and the disk I I located therein to enter the current magnetic pole piece 9. This magnetic flux returns to the voltage magnetic pole piece through a righthand arm 21 of the magnetic structure I.

Current windings 29 and 3I are disposed respectively about the current magnetic pole pieces I and 9. These windings are connected in series and are oppositely poled so that when the winding 29 directs a magnetomotive force downwardly in the current magnetic polepiece I, the winding 3| establishes an equal upwardly-directed ma netomotive force in the current magnetic pole piece 9. The resulting flowof magnetic flux is represented in part by a dotted line 33 which has an instantaneous direction of flow represented by an arrow. shown in Fig. 1, the magnetic flux represented by the dotted line 33 enters the air gap I5 from thecurrent magnetic pole piece 9, h

traverses the disk I! and may possibly enter the voltage magnetic pole piece '3. The magnetic flux then bends downwardly to cross the disk I! again and'enters the current magnetic pole piece 'I. From the last-mentioned pole piece, the magnetic flux returns to the magnetic pole piece 9 through an appropriate part of the magnetic structure I.

Additionalcurrent magnetic flux may flow in paths similar to those represented by the dotted lines 2I and 23. For the assumed instantaneous conditions, current magnetic flux traversing the path represented by the dotted line 23 would flow in a direction opposite to that represented by the arrow on the line.

In Order adjust the light-load performance 7'13 of the watthour meter, a light-load adjuster 35 in the form 'of an electroconductive plate is positioned in the air gap I5 adjacent the pole face 5.

,of the watthour meter, a magnetic shunt 31 is positioned between the current magnetic pole pieces I and Sadjacent their pole faces. The magnetic shuntmay be spaced from the associated pole pieces by means of a non-magnetic plate 39 to which the shunt is secured by means of a rivet 4|.

The parts of Fig. 1 which thus far have been specifically described are all well known and well understood in the art. For this reason, an extended discussion of the parts thus far specifically described is believed to be unnecessary. When the voltage winding I9 and the current windings 29 and 3| are energized, it is desirable that the magnetic fluxes therefrom which traverse the air gap I5 have a predetermined phase relationship. For a watthour meter, this phase relationship should be such that at unity power factor, the two magnetic fluxes are in quadrature. Although the voltage winding l9 may have substantialinductance for the .purpose of lagging its voltage magnetic flux substantially behind the voltage applied to the winding, such lagging does not suflice to establish the desired phase relationship between the voltage and current magnetic fluxes.

In accordance with the invention, a lagging or quadrature member is disposed in the air gap I5 for the pin'pose of lagging one or both of the magnetic fluxes. This lagging member may be located at any position in the air gap either adjacent the current magnetic pole piece or the voltage magnetic pole pieces wherein it intercepts or surrounds the desired magnetic flux. In the specific embodiment of Fig. l, a lagging member 43 rests on the pole faces H and I3 and conveniently may be secured to the magnetic shunt 31 by the rivet With such a construction, the magnetic shunt 31 and the lagging member 43 may be assembled as a unit and installed in the magnetic structure or removed therefrom as a unit. For example, the non-magnetic plate 39 may be received in a dove-tailed slot formed by the current magnetic pole pieces I and 3 and may be frictionally retained therein.

The configuration of the lagging member 43 is clearly shown in Figs. 2 and 3. The lagging member includes an annular electroconductive rim 45. Good results have been'obtained with annular rims having. rectangular or square perimeters but in the preferred embodiment of Fig. 2 a circular annular rim is disclosed. The annular rim is connected at spaced points by means of an electroconductive bar 41. The lagging member may be mounted for movement relative to the associated magnetic structure in any desired manner. As previously pointed out, in a preferred embodiment of the invention the lagging member 43 is secured rotatably to the magnetic shunt 31 by means of the rivet M which passes through the electroconductive bar 41. Angular movement of the electroconductive lagging member 43 about the rivet 4I may be through any desired angle. A stop 43 is provided for limiting the angular movement of the lagging member 43 to the extreme positions illustrated in Figs. 2 and 3 which differ from each other by By inspection of Fig. 1, it will be observed that the stop 49 engages the current magnetic pole pieces in the limiting positions ofthe lagging member 43. If desired, a scale (not shown) may cooperate with the stop to indicate the angular position of the lagging member. I

If the lagging member were perfectly symmetrical, for example, a disk of electroconductive material, it would serve to lag magnetic fluxes traversing the disks substantially equally for all annular positions of the disk about its axis of rotation. In order to provide an adjustment, some asymmetry is provided. In the present case, such asymmetry is provided by the use of a single bar 41 which divides the lagging member in two parts each havingan opening 5| or 53. Theresultingstructure has substantiallya figure of. eight configuration which isclearly apparent from Figs. 2 and 3.; I

The operation of the lagging member may be understood more clearly'by tracing the paths of the magnetic fluxes relative to the lagging member. By inspection of Fig. 2, it'will be observed that the voltage magnetic fluxes represented by the dotted lines 2I and 23 both enter the paper in Fig. 2 in the same direction. Such voltage magnetic fluxes tends to induce an electromotive force in the rim 45 which directs current around the rim. Consequently, the rim 45'operates substantially as a'conventional lag loop to lag the eg-melt metrical about its axis offrotation.

The-current magnetic 'fiux also is shown in Fig. 2. It will be noted that such "magnetic fiuX emerges'from the paper towards the observer at a points-3b "and re-enters the paper traveling awa rrom the observer ata point 33a.

With respect to the current magnetic flux, the lagging member may be considered to comprise two 'el'ectroconductive loops, one loop having the "opening 51 and the second loop having the opening 53. The bar #1 is common to both loops. For the assumed conditions in Fig. 2, all current magnetic flux entering the opening is directed into the paper and travels away from the observer; All current magnetic flux entering the opening *53 emerges from the paper towards the observer. The resulting electromctive forces producecurrent flow in the same direction throughthe bar 41 and the resultant cur- 'rent divides between the two halves of the rim 55 which connect the endscf the bar in parallel. Consequently, the current magnetic flux also is la ged by the lagging member 63.

' Adjustment of the lagging member 43 to the positionillustrated in Fig. 3 has substantially no effect on the lagging of the voltage magnetic flux. However, a brief consideration of Fig. 3 will show that the lagging member 43 no longer lags appreciablythe current magnetic flux. It will be noted tha't'in Fig.3 equal amounts of current magneticflu'xpa'ss in opposite directions through each of the openings 5| and 53. Consequently, the laggingof current magnetic flux is a minimum with the lagging member 43 in the position i1- lustrated'in Fig. 3.

It maybe observed that some lagging of current magnetic flux takes place even with the lagging member in the position illustrated in 3for'the reason that the lagging member is made of electroconductive material and local eddy currents are produced therein by magnetic flux which directly cuts or traverses such electroconductive material. However, such lagging is small comj'pa'red to "the lagging obtained by magnetic flux passing through the openings 5| and 53 for the case illustrated by Fig. 2 and is substantially unijform'for all positions of the lagging member.

Fromthe-foregoing discussion, it will be clear fthatl'by adjusting the lagging member between the positions illustrated in Figs. 2 and 3, the phase displacement between the current and voltage magneticfiuxes may be adjusted to a desired value, the lagging member may be retained in any position'of adjustment in any desired manne'rffor example, the rivet 4| may secure the lagging member frictionally to the shunt sufficiently toprevent accidental rotation thereof.

'In'some cases,'adjustment of the lagging memberma'y'afiect the light-load adjustment of the associated watthour meter. This is for the reason"that"thepatternof the magnetic fluxes is cha'nged'slightly asa result of rotation of the lagging member. If "desired, the sheets of the lagging member on the light-load adjustment may be substantially eliminated by properly shiftingthe"lagging member during its adjustment. "Suchshifting'maybe'eifected by (1) displacing the axis 'ofrotation of the laggingmember from fthe'center ofthe shuntor center line of the magany desired manner. =cut or punched as an integral unit from a sheet genes-aware,ere) by mounting the lagging m of copper, brass or :bronze'having the desired member "for rotation about an axis which is dis placed from the axis of 'the rim, or (3) bye-cormbinationof such displacements. For example'in Fig.4, a'lag'gin'g member m is shown which correspondsto'the laggingm'emb'e'r '43 of Figs- 1 to 3 andwhich has annular rim l'dweorresponding to the rim {45 ofFigs. 2 and '3. Hewever,'the-1agging member '43a is rotatably securedtothe shunt 3! by a rivet Ma, which is displaced by a distance A from'the axis 'of the circular rimll'm. and from the center ofthe'shunt 31; consequently, 'as the lagging member "43a. is rotated'about the rivet am, it not only is anginarly adjusted about the axis of the'rim lfia 'ibu't 'it is shiftedwith respect thereto. By proper selection of "the 'dist'arice and the direction o'f'di'splacement 'of'the rivet 4121 from the axis of the'rim 45a and f'rom the center of the shunt, the shift of the lagging member "no as it is adjusted may be selected to make the light-load adj ustment o'f 'the'tvatthour meter substantially independent of adjustment ofthe lag ging member. 'InFig. 4,-the axis 'ei rotation oi the lagging member is'displaced fromthe center of the shout. and from the axis'of the ii'm b'y the same distance.

In Fig. '5 a lagging member 4% "is provided which is similar to the lagging member 43. The embodiment of Fig. '5 differs from that OI 2 only in the mounting of the lagging member 4312 by the rivet 4-! for rotation about an axis which is displaced' from the axis of the rim 'of th'e lagging member "by a distance 18. It should be noted that'the rivet M isdisposed at the'center of the shunt Al. By proper selection or the magnitude of the distance "B and ofthe direction of displacement, light-load compensation maybe provided.

Referring noW'to Fig. 6, a lagging member 113c is disclosed which is similar to the "lagging member 43 of Fig. 2. However, in Fig. 6, the lagging member is mounted suit-ably on a support fil A or rotation-about a desired axis, 'such as the ax'i's of its rim, relative to'th'e su ortel. Foremmpiel, lips'B-B are secured to the support-and are bent over therimof the lagging member to guid'e'it for rotation. In effect, the three'lips illustrated define a channel through which the r'i'mbf the lagging member 43 maybe rotated withoutnecessitatirig a centrally disposed pivot.

The support 6! is mounted for reciprocation 'in the direction of the arrows C relative to the magneticv structure 'I in any suitable manner. For the purpose of illustration, a screw 651s mounted for'rota'tion in a bracket B'I'which is's'ecured "to the magnetic structure. The screw :55 is in threaded engagement with the support 51. Rotation of the screw reciprocates the :support relative to the magnetic-structure as desired.

By rotation of the lagging member 430, the

phaseangle' may-be adjusted. The laggin mem member to the su port.

Recip'rocation of the support 6! moves the lagging member to adjust the light-load per- Consequently, the ad- Thelaggingmember 43 may be constructed in For example, it may be 2&51253 impedance characteristics, Alternatively, the rim and barof the lagging member, may be constructed separately and ,may be joined subsequently in anysuitable manneras by soldering or brazing. For example-in Fig. 4 the rim 45a and its associated electroconductive bar 41a may be separately cut from suitablematerial and may be secured to each otheri any suitable manner. i

From the consideration of'Figs. 2; and 3, it will be recalled that the current flowing" through the bar 41 is produced substantially onlybythecurrent magnetic fiux.-. Since this is the case the impedance characteristics of the bar vI! may difier from those of. the rim 45 for the purpose 01' providing additional desirable performance characteristics of the watthour. meter. .For example let it be assumed that in Fig. 4 the rim 45a is constructed of a first material such as bronze and that the bar 41a is constructed of copper or other material having a temperature coefiicient of resistance substantially higher than that of the first material. By proper selection of the temperature coefilcients of resistance, the lagging member 43a. may be designedtoprovide the temperature control described in the Oman Patent 1,764,339.

Although the invention has been described with reference to certain specific embodiments thereof, numerous embodiments thereof are possible. Therefore, the appended claims have been drafted to cover all modifications and embodiments fallingwithin the spirit and scope of the invention.

I claim as my invention: I

1. In an alternating-current device, means effective when energized for producing a first alternating magnetic flux, means effective when energized for producing a second alternating magnetic flux cooperating with the first alternating magnetic fiux to establish a shifting magnetic field, and means for controlling the phase relationship between the magnetic fluxes, said last-named means comprising a lagging member for lagging the first alternating magnetic fiux by an amount dependent on the angular position of the lagging member relative to the first alternating magnetic flux about an axis, and means mounting the lagging member for angular movement relative to the first alternating magnetic flux about said axis, the lagging member being positioned to lag the second alternating magnetic fiux, and the lagging member being configured to, lag the second alternating magnetic flux by substantially the same amount for all angular positions of the lagging member about theaxis.

2. An alternating current device comprising means efiective when energized for producing magnetic flux and a lagging member for the magnetic fiux, said lag i g member including an electroconductive substantially circular rim and an elect-roconductive bar extending diametrically across said rim.

3. A device as set forth in claim 2 wherein said lagging member is mounted for rotation relameans effective when energized for producing two magnetic fluxes which cooperate to establish a shifting magnetic field, an electroconductive armature disposed in the magnetic field, means mounting thearmature for movement in response the shifting ma'gnetlc'field; a lagging member disposed inthe path of at. least one of the magnetic fluxes,- 'said lagging member being configured to change the amount of logging of the associated magnetic fiux in response to rotation of the lagging member relative to the first means about a'first axis, and means mounting the lagging member for movement through a predetermined path, said movement comprising a rotation of the lagging member about the axis and a simultaneous shifting movement of the lagging member relative to the axis which bears a. predetermined relation to the rotation of the lagging member for simultaneously changing the lagging and the portion of the magnetic fiux which is subject to. control by the lagging member.

5. In an alternatingdevice responsive to the relation between two alternating quantities, means effective when energized for producing two magnetic fluxes which cooperate to establish a shifting magnetic field, an electroconducti've armature disposed in the magnetic field, means mounting the armature for movement in response to the shifting magnetic field, a lagging member disposed in the path of at leastone of the magnetic fluxes, said lagging member being configured to change the amount of lagging of the associated magnetic flux in response to rotation of the lagging member relative to the first means about a first axis, and means mounting the lagging member for rotation about. a second axis displaced from the first axis to change the angular position of the lagging member about the first axis and simultaneously to shift the lagging member relative to the first axis, whereby the torque applied to said armature is modified both by the resulting change in lagging and by the resulting change in the portion of the magnetic flux which is subject to controlby the lagging member.

6. In an alternating current device, a first magnetic pole piece having a first pole face, a pair of spaced second pole pieces having second pole faces disposed substantially in a'common plane said second pole faces being spaced from the first pole piece to define an air gap,.an electroconductive armature disposed in said air gap, means mounting the armature for rotation relative to the pole pieces, first winding means eifective when energized by alternating current for directing alternatin first magnetic fiux in a path which extends from the first pole face through the armature to the second pole faces in parallel, second winding means effective when energized by alternating current for directing alternating second magnetic fiux through two paths which extend from the second pole faces through the armature in substantially opposite directions, an electroconductive lagging member having two openings establishing. a figure-of-eight configuration, and means mounting the lagging member for movement from a position wherein the second magnetic flux is' directed in a single direction through each of the openings in the lagging member, the directions in the two openings being substantially opposite, to a position wherein said second magnetic flux has two portions oppositely directed through each of the openings.

7. A device as claimed in claim 6 wherein the first magnetic flux is directed through the two openings of the lagging member in the same direction.

8. In an alternating current device, a first magnetic pole piece having a first pole face, a pair of spaced second polepieces, having second pole faces disposed substantially .in a common plane said second pole faces being spaced from the first pole piece to define an air gap, an electroconductive armature disposed in said air gap, means mounting the armature for rotation relative to the pole pieces, first winding means efiective when energized by alternating current for directing alternating first magnetic fiux in a path which extends from the first pole face through the armature to the second pole faces in parallel, second winding means effective when energized by alternating current for directing alternating second magnetic fiux through a path which extends from one of the second pole faces through the armature to the other of the second pole faces, an electroconductive lagging member having an annular electroconductive rim and an electroconductive bar extending diametrically across said rim to establish two openings within the rim thereby providing a structure having substantially a figure-of-eight configuration, means mounting the lagging member in the air gap for angular movement about an axis passing through the bar, said lagging member in one position having the second magnetic flux directed through a first one of the openings over the bar and through the second one of the openings to establish a fiux loop around said bar for lagging the second magnetic flux, said lagging member being rotatable about the axis to vary the magnitude of the fiux in said fiux loop.

9. An alternating-current device as set forth in claim 8, wherein said first magnetic fiux is directed through said rim to lag the first magnetic fiux.

10. An alternating-current device as set forth in claim 9 wherein the rim and the bar have different temperature coefiicients of impedance.

11. An alternating-current device as set forth in claim 8 wherein the device includes a lightload adjuster and said axis is displaced from the axis of symmetry of the lagging member in a, direction and by an amount sufiicient to make the light-load response of the device substantially independent of the angular position of the lagging member about the axis of rotation.

12. In an alternating-current watthour meter, a magnetic structure comprising a voltage magnetic pole piece having a voltage pole face, and a pair of spaced current magnetic pole pieces having current pole faces disposed in a common plane spaced from the voltage pole face to define an air gap therebetween, an electroconductive armature positioned in the air gap, means mounting the armature for rotation relative to the magnetic structure, a voltage winding associated with the voltage magnetic pole piece, said winding being effective when energized by an alternating voltage for directing alternating voltage magnetic flux between the voltage pole face and the current pole faces in parallel, current windings associated with the current magnetic pole pieces, said current windings being efiective when energized by an alternating current for directing alternating current magnetic flux in series through a first path which extends from one of the current pole faces through the armature and through a second path which extends through the armature to the other of the current pole faces, and a lagging member having a circular electroconductiverim positioned in the air gap to surround substantial portions of the voltage magnetic fiux and said two paths, and an electroconductive bar extending between said paths to connect spaced points of said rim.

13. A meter as defined in claim 12' wherein means mount said lagging member for movement relative to the magnetic structure to a new position wherein said bar substantially intercepts at least one of the paths.

14. A meter as defined in claim 12 including means mounting the lagging member for rotation substantially about the axis of said rim.

15. A meter as defined in claim 12 including means mounting the lagging member for rotation about an axis parallel to and displaced from the axis of the rim for the purpose of making the light-load adjustment of the meter independent of the position of the lagging member.

16. An alternating-current watthour means comprising a magnetic structure effective when energized for establishing a shifting magnetic field, an armature positioned in the magnetic field for movement in response thereto relative to the magnetic structure, a magnetic shunt detachably secured to the magnetic structure for controlling the response of the armature to energization of the magnetic structure, a lagging member for adjustably controlling the phase relationship between the components of the magnetic field in accordance with the angular position of the lagging member about an axis, and means rotatably securing the lagging member to the shunt for installation or removal therewith as a unit relative to the magnetic structure.

1'7. In an alternating-current device, means effective when energized for producing a first alternating magnetic flux, means effective when energized for producing a second alternating magnetic fiux cooperating with the first alternating magnetic flux to establish a shifting magnetic field, and means for controlling the phase relationship between the magnetic fluxes, said last-named means comprising a lagging member for lagging the first alternating magnetic fiux by an amount dependent on the angular position of the lagging member relative to the first alternating magnetic flux about an axis passing through the lagging member within the periphery of the lagging member and within the space traversed by the first alternating magnetic flux, and means mounting the lagging member for angular movement relative to the first alternating magnetic fiux about said axis.

18. A device as claimed in claim 1'7 wherein the lagging member is also positioned to lag the second magnetic flux.

19. An alternating current device comprising means effective when energized for producing magnetic 'fiux and a lagging member for the magnetic fiux, said lagging member including an electroconductive closed loop and an electroconductive element extending between spaced points on the loop, said loop and element havin different temperature coefiicients of impedance.

RICHARD M. LEIPPE.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,518,196 Harris Dec. 9, 1924 1,856,554 Harris May 3, 1932 2,146,606 Trekell Feb. 7, 1939 2,363,284 Barnes Nov. 21, 1944 2,365,588 Petsinger Dec. 19, 1944 FOREIGN PATENTS Number Country Date 691,375 Germany May 24, 1940 

